We are interested in moving a subscriber for a CCM 5.1 across our WAN for survivabiltiy.
How much bandwidth can I expect to be used by the CCM to keep current, or how much should we have? We have a small system of less then 200 phones, that rarely changes.
Database replication between publisher uses best effort (DSCP=0). The only recommendation from cisco for the replication traffic between pub and sub is that maximum RTT of 40 ms, 20 ms in either direction.
So based on your WAN setup, you should be fine enough, check the ping results across the wan and make sure the RTT is under 40 ms.